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Abstract Background Five-guaranteed elderly individuals are a special group of the elderly Chinese population faced with unique challenges; these individuals lack any financial resources (including support by relatives), and are solely reliant on the government to provide food, clothing, medical care, and housing as well as burials. In this article, we aim to investigate mood problems (depression, anxiety) and cognitive functioning in Five-guaranteed elderly individuals, and to validate the effectiveness of two promising interventions, graphene far-infrared intervention (GFII; an exploratory and noninvasive technique) and social network intervention (SNI), for elderly people to lay the foundation for future social service work. Methods To address the emotional and cognitive difficulties experienced by this special group, we designed this study, which is the first to apply GFII in this population. We also administered SNI given the social isolation of these individuals, in addition to a corresponding control group. 108 elderly individuals in 3 elder care facilities were screened to evaluate eligibility to participate in the current study, including 44 from Facility A (allocated to the GFII group), 43 from Facility B (allocated to the SNI group), and 21 from Facility C (allocated to the control group). GFII lasts for four weeks, with professionally trained carers putting on and removing intervention caps for half an hour each day. SNI lasts for three weeks, three times a week, and consists of a total of nine themed activities. The length of an activity is 90 min. We also did pre- and post-test comparisons of depression, anxiety and cognition in each group of older adults. Results The results showed that GFII led to immediate improvements in anxiety and cognitive impairment in the five-guaranteed elderly individuals, and the improvement in cognitive function was sustained over time. Moreover, SNI group showed significant improvements in cognitive function after the intervention period. Conclusions The GFII is a promising intervention that can be applied to intervene in cognitive and mood disorders in older adults. The GFII has short-term interventions for anxiety in older adults, but long-term effects for cognitive impairment. SNI also had an interventional effect on cognition.

Abstract Thermally activated delayed fluorescence (TADF) materials have numerous applications in energy conversion and luminescent imaging. However, they are typically achieved as metal‐organic complexes or pure organic molecules. Herein, we report the largest Au‐Ag‐oxo nanoclusters to date, Au18Ag26(R1COO)12(R2C≡C)24(μ4‐O)2(μ3‐O)2 (Au18Ag26, where R1 = CH3‐, Ph‐, CHOPh‐ or CF3Ph‐; R2 = Ph‐ or FPh‐). These nanoclusters exhibit exceptional TADF properties, including a small S1‐T1 energy gap of 55.5 meV, a high absolute photoluminescence quantum yield of 86.7%, and a microseconds TADF decay time of 1.6 μs at ambient temperature. Meanwhile, Au18Ag26 shows outstanding stability against oxygen quenching and ambient conditions. Atomic level analysis reveals the strong π⋯π and C‐H⋯π interactions from the aromatic alkynyl ligands and the enhancement of metal‐oxygen‐metal interactions by centrally coordinated O2−. Modeling of the electronic structure shows spatially separated highest occupied molecular orbital and lowest unoccupied molecular orbital, which promote charge transfer from the ligand shell, predominantly carboxylate ligands, to O2−‐embedded metal core. Furthermore, TADF Au‐Ag‐oxo nanoclusters exhibit promising radioluminescence properties, which we demonstrate for X‐ray imaging. Our work paves the way for the design of TADF materials based on large metal nanoclusters for light‐emission and radioluminescence applications.

Summary: The atomically precise metal electrocatalysts for driving CO2 reduction reactions are eagerly pursued as they are model systems to identify the active sites, understand the reaction mechanism, and further guide the exploration of efficient and practical metal nanocatalysts. Reported herein is a nanocluster-based electrocatalyst for CO2 reduction, which features a clear geometric and electronic structure, and more importantly excellent performance. The nanocatalysts with the molecular formula of [Ag17Cu10(dppm)4(PhC≡C)20H4]3+ have been obtained in a facile way. The unique metal framework of the cluster, with silver, copper, and hydride included, and dedicated surface structure, with strong (dppm) and labile (alkynyl) ligands coordinated, endow the cluster with excellent performance in electrochemical CO2 reduction reaction to CO. With the atomically precise electrocatalysts in hand, not only high reactivity and selectivity (Faradaic efficiency for CO up to 91.6%) but also long-term stability (24 h), are achieved.

It remains a challenge to fabricate metal catalysts with interfacial active sites distributed on the whole two-dimensional (2D) surface of metal nanoparticles. Here the authors demonstrate that the overgrowth of atomic-thick porous Cu2O on Pd readily creates an unprecedented 2D catalytically active metal-support interface with significantly enhanced catalysis toward the semi-hydrogenation of alkynes.

Abstract The flexible printed electronics (e.g., wearable devices, roll-up displays, heating circuits, radio frequency identification (RFID) tags) calls for high-conductivity and low-cost materials, particularly for copper pastes. It is still a big challenge to develop reliable copper pastes for both antioxidant and high-conductivity flexible printed films and lines. In this work, an antioxidant copper paste was achieved using copper microflakes with surface passivation by formate ions and thiols, with high conductivity of 13400 S cm−1 (the same order of magnitude of silver pastes, 1.8–2.5 × 104 S cm−1). The universal applications of as-prepared copper paste in flexible printed electronics (e.g., electromagnetic interference (EMI) shielding films, anti-fog films, and RFID tags) via screen printing and curing at 170 °C under ambient atmosphere were demonstrated. The as-printed electronics showed high performance in flexibility, stability, and reliability. This work shows the great potential of anti-oxidation copper pastes in low-cost flexible printed electronics for commercial usage.

Accumulated halide defects on the buried interfaces of halide perovskite layers have exacerbated undesirable nonradiative recombination in the n–i–p perovskite photovoltaics, but are challenging to be passivated—the commonly used passivation molecules at buried interfaces of perovskite layers would be inevitably eroded in the solution processes of perovskite deposition. Regarding the solvent incompatibility, herein, the ZnO–EA/SnO2–Cl electron transfer layers (ETLs) terminated with functional sites (i.e., ethanolamine (EA) ligands on ZnO and Cl− ions on SnO2) to spontaneously heal the buried interfaces of perovskite layers are customized. The specialties of ZnO–EA/SnO2–Cl for defect passivation are revealed: 1) formation of ZnO–EA–Pb2+ coherent interlayers at the EA‐terminated ZnO‐perovskite interfaces effectively offsets the I vacancy defects of perovskites; and 2) spontaneous halide exchange between Cl−‐terminated SnO2 and unstable I−‐terminated perovskites enables the formation of FA2Sn(ICl)6‐like coherent interlayers. Thus, the customized termination of ETLs’ surface reduces the halide‐defect‐triggered nonradiative recombination at the buried surfaces of perovskite, enabling the fabricated n–i–p planar modules (6 × 6 cm2) with power conversion efficiencies approaching 18% and elevated stability. These findings provide desirable guidelines for interfacial carrier transport between perovskites and ETLs.

Precious metal catalysts are the cornerstone of many industrial processes. Replacing precious metal catalysts with earth-abundant metals is one of key challenges for the green and sustainable development of chemical industry. We report in this work a surprisingly effective strategy toward the development of cost-effective, air-stable, and efficient Ni catalysts by simple surface modification with thiols. The as-prepared catalysts exhibit unprecedentedly high activity and selectivity in the reductive amination of aldehydes/ketones. The thiol modification can not only prevent the deep oxidation of Ni surface to endow the catalyst with long shelf life in air but can also allow the reductive amination to proceed via a non-contact mechanism to selectively produce primary amines. The catalytic performance is far superior to that of precious and non-precious metal catalysts reported in the literature. The wide application scope and high catalytic performance of the developed Ni catalysts make them highly promising for the low-cost, green production of high-value amines in chemical industry.

Abstract Although the perovskite solar cells have been developed rapidly, the industrialization of perovskite photovoltaics is still facing challenges, especially considering their stability issues. Here, the new type of benzimidazolium salt, N,N′‐dialkylbenzimidazolium iodide, is proposed and functionalized to convert the three‐dimensional (3D) FACs‐perovskite films into one‐dimensional (1D) capping layer topped 1D/3D structure either in individual device or module levels. This conformal interface modulation demonstrates that not only can effectively stabilize FACs‐based perovskite films by inhibiting the lateral and vertical iodide diffusions in devices or modules, ensuring an excellent operation and environmental stability, but also provides an excellent charge transporting channel through the well‐designed 1D crystal structure. Consequently, efficient device performance with power conversion efficiency up to 24.3% is readily achieved. And the large‐area perovskite solar modules with high efficiency (19.6% for the active areas of 18 cm2) and long‐term stability (about 500 h in AM 1.5G illumination or about 1000 h under double‐85 conditions) are also successfully verified.

Abstract Power conversion efficiency (PCE) and long‐term stability are two vital issues for perovskite solar cells (PSCs). However, there is still a lack of suitable hole transport layers (HTLs) to endow PSCs with both high efficiency and stability. Here, NiOx nanoparticles are promoted as an efficient and 85 °C/85%‐stable inorganic HTL for high‐performance n‐i‐p PSCs, with the introduction of perovskite quantum dots (QDs) between perovskite and NiOx as systematic interfacial engineering. The QD intercalation enhances film morphology and assembly regulation of NiOx HTLs . Due to structure–function correlations, hole mobility within NiOx HTL is improved. And the hole extraction from perovskite to NiOx is also facilitated, resulting from reduced trap states and optimized energy level alignments. Hence, the promoted NiOx‐based n‐i‐p PSCs exhibit high PCE (21.59%) and excellent stability (sustaining 85 °C aging in air without encapsulation). Furthermore, encapsulated solar modules with QDs‐promoted NiOx HTLs show impressive stability during 85 °C/85% aging test for 1000 hours. With high transparency, QDs‐promoted NiOx is also demonstrated to be an advanced HTL for semitransparent PSCs. This work develops promising NiOx inorganic HTL in n‐i‐p PSCs for manufacturing next‐generation photovoltaic devices.

Bottom-up design of functional device components based on nanometer-sized building blocks relies on accurate control of their self-assembly behavior. Here, the authors demonstrate a solvent-mediated polymerization of atom-precise gold–silver nanoclusters into macroscopic single crystals with highly anisotropic p-type semiconducting characteristics.

Size effect plays a crucial role in catalytic hydrogenation. The highly dispersed ultrasmall clusters with a limited number of metal atoms are one candidate of the next generation catalysts that bridge the single-atom metal catalysts and metal nanoparticles. However, for the unfavorable electronic property and their interaction with the substrates, they usually exhibit sluggish activity. Taking advantage of the small size, their catalytic property would be mediated by surface binding species. The combination of metal cluster coordination chemistry brings new opportunity. CO poisoning is notorious for Pt group metal catalysts as the strong adsorption of CO would block the active centers. In this work, we will demonstrate that CO could serve as a promoter for the catalytic hydrogenation when ultrasmall Pd clusters are employed. By means of DFT calculations, we show that Pdn n=2‐147 clusters display sluggish activity for hydrogenation due to the too strong binding of hydrogen atom and reaction intermediates thereon, whereas introducing CO would reduce the binding energies of vicinal sites, thus enhancing the hydrogenation reaction. Experimentally, supported Pd2CO catalysts are fabricated by depositing preestablished [Pd2(μ-CO)2Cl4]2- clusters on oxides and demonstrated as an outstanding catalyst for the hydrogenation of styrene. The promoting effect of CO is further verified experimentally by removing and reintroducing a proper amount of CO on the Pd cluster catalysts.

Metal-support interaction plays an important role in heterogeneous catalysis, but silica has been rarely reported as an effective support to create active metal-support interfaces for promoting catalytic reactions. Here, the authors discover that Cu/SiO2 interface creates an exceptional effect to promote catalytic hydrogenation of esters.

Atomic shell closure and electronic shell closure are generally considered to be competing effects in stabilizing magic-sized metal nanoclusters. Here, the authors show, by co-crystallizing two differently-sized clusters, that both mechanisms can work concurrently during magic cluster synthesis.

Translating high-resolution imaging methods to the curved organic surface of a nanoparticle has been challenging. Here, the authors are able to spatially resolve the sub-molecular surface details of a silver nanocluster by comparing scanning tunneling microscopy images and simulated topography data through a pattern recognition algorithm.

One of the challenges facing lithium-sulfur batteries is to develop cathodes with high mass and high volume loading. Here the authors show that two-dimensional carbon yolk-shell nanosheets are promising sulfur host materials, enabling stable battery cells with high energy density.

The structure of nanoparticles strongly influences their properties. Here, the authors use single crystal X-ray diffraction to resolve the crystal structures of Ag136 and Ag374nanoparticles, enabling the observation of local structure distortion and the lower size limit of surface plasmon resonance.

Protein subunits on the capsids of icosahedral viruses can form patterns with rotational symmetry, which are difficult to recreate in the laboratory. Here the authors report a strategy to construct 3D chiral polyhedra with rotational faces from 2D chiral truxene-based units through dynamic covalent chemistry.

Energy migrations at metal nanomaterial surfaces are fundamentally important to heterogeneous reactions. Here, the authors employ ultrafast vibrational spectroscopy to show two distinctive energy migration pathways of monolayer adsorbate molecules on differently sized metal nanoparticle surfaces.

The article focuses on supported atomically dispersed palladium (Pd) catalysis for direct alkoxylation and allylic alkylation, emphasizing the catalyst's efficiency and unique mechanism. It discusses the utilization of atomically dispersed Pd on titanium dioxide (TiO2) nanosheets for direct allylic alkylation from allylic alcohols, highlighting the role of hydrogen bonding at the organic-inorganic interface in facilitating the reaction.